You can increase the 40 coins limit by leveling up or collecting prizes.
Assuming you have currently 40 coins limit. It will take 360 minutes or 6 hours to have full coins capacity or 40 coins.

Coin Dozer: Pirates Tip#2: Watch Ads
Watch Ads specially if you can get gems for free. Gems are valuable currency in the game, it will help you obtain prizes and puzzle items to improve your gameplay experience.

Coin Dozer: Pirates Tip#3: Coin Wall
You can get Coin Wall through boost, power-up and level up. Don't buy Coin Wall because it is expensive and you can get it anyway through other options.
Maximize your income potential when you get the coin wall. You must have a lot of coins to maximize it's use because Coin Wall has a time limit.
Look for potential Coin Wall such as power-ups and level up. Don't forget to save coins, so that you can maximize Coin Wall earning potential.

Coin Dozer: Pirates Tip#4: 1 Coin at a time
1 Coin at a time is most efficient compared to putting many coins at the same time.

Coin Dozer: Pirates Tip#5: Avoid buying Coin Walls
Avoid buying Coin Walls, buy a box of prizes instead.
There are many rewards when you get a lot of prizes such as leveling, more coins, more bonuses and etc.